From what I can tell in the horseman fight, it's a lot of shield-and-renew on the DPS and ranged crowd and a lot of renew-and-penance on the warrior tank. Pain Suppression on the tank and Power Infusion on a caster. Granted, being a shield-machine doesn't help with a warrior that needs to take it on the chin for aggro purposes, but having to worry very little about the rest of the group because of the sheer power of your heals coupled with the best castable mitigation in the game makes 5-mans a breeze, currently. Of course, everything is a breeze right now.
I will say that Holy Nova is a lot more impressive at 70 than it was at 60. It's not something to spam, but for topping up a group that's taken a couple of rounds of AoE and getting 3/5 crits which set of Aegis is really cool. Plus, Nova's utility in a Tank-and-AoE situation cannot be denied. AoE events in instances should be an utter breeze with you standing in the middle laying out 10-15 rounds of 600 HP heals and 400 damage.
I know my comment is slightly off-topic, but Discipline Priests really need to get some love now that it's a very viable spec in 5 mans. I think their utility in a raid won't be ignored.